mountune Focus ST MRX Turbocharger Upgrade
The mountune MRX Turbocharger Upgrade for the 2013-18 Focus ST offers greater power output with minimal increase in turbocharger lag, which greatly enhances the driving experience.
Tested and validated over thousands of miles for durability and performance, the mountune MRX Turbocharger Upgrade includes all required hardware, fittings and hoses. This upgrade does not require any fuel system upgrades and is compatible with both 91, 93, and 94 octane fuel. The mountune MRX Focus Turbocharger Upgrade has been developed for those that desire a fully engineered upgrade that provides an optimized power band. Unlike other upgrades that deliver just peak or high RPM power, the mountune MRX Turbocharger Upgrade offers performance throughout the entire power band ensuring a very responsive and drivable car. The MRX Turbocharger Upgrade is designed for those that are looking for well balanced yet extremely powerful performance derived from years of developing race winning Ford 4 cylinder turbocharged engines.
The standard BorgWarner K03 based turbocharger, as found on the Ford EcoBoost engine in the Focus ST, is a capable turbocharger with excellent response and power potential up to the low 300bhp range. For power outputs above that level, a larger turbocharger is required.
The mountune MRX Turbocharger Upgrade is engineered around the BorgWarner EFR turbocharger platform for seamless integration and excellent response and performance. Developed as a complete system with everything available from one source ensures the performance and quality you’ve come to expect from mountune. Because of the unique Low Inertia Gamma-Ti Turbine Wheel, power comes on strong with amazing response and virtually no turbo lag. Integrated recirculation valve ensures smooth drivability and throttle transition. We rely on the BorgWarner EFR 6258A for the foundation of the MRX kit. The EFR 6258A lends itself well to incredible response with virtually no lag while producing incredible power and a very drivable car. For those that wish to go further with slightly higher power levels, the MRX kit is available with the BorgWarner EFR 6758 or EFR 7163 Turbocharger, additional cost may apply.
Power Graph with 6258A Turbocharger
Turbocharger Features:
- Dual Row Ceramic Ball Bearings - lowest friction and fastest spool/response
- Water Cooled Center Section
- Double seals on both turbine and compressor end for extreme durability and resistance to any oil seepage
- Boost Control Solenoid Valve Integrated to Compressor Housing
- Integrated Speed Sensor mounting provisions
- Low Inertia Gamma- Ti Turbine Wheel
- Stainless Steel Turbine Housing
Kit Features:
- mountune Ni Resist turbocharger adapter
- Preformed coolant hard lines ensure trouble free installation and performance
- Mounting brackets to retain original heat shield
- 6-ply reinforced silicone primary compressor intake hose assembly - Allows for maximum flow while minimizing false knock caused by metal to metal contact
- BorgWarner Integrated recirculation valve ensures smooth OE operation and perfect drivability. Optional mountune recirculation valve can be installed
What's included:
1x mountune Ni-resist Cast Turbo Adapter Assembly
1x mountune Ultra Duty T25 Turbine Inlet Gasket
1x BorgWarner EFR-6258A Turbocharger Assembly (BorgWarner EFR-6758 or EFR-7163 optional)
1x mountune Motorsport Downpipe
1x mountune 6-Ply Compressor Inlet Hose Assembly
1x Stainless Steel Hose Clamp – SAE #52
1x Stainless Steel Hose Clamp – SAE #44
1x Turbocharger Oil Inlet Hose Assembly
1x Adapter Fitting, M12x1.5 to -4
1x Crush Washer, M12
1x Adapter Fitting, M14x1.5 to -6
1x Crush Washer, M14
1x Water Pipe #1, Block to Turbo
1x Water Pipe #2, Water Neck to Turbo
1x Tube Adapter, Turbo Oil Drain
1x Gasket, Oil Return Tube
1x mountune 5-Ply Compressor Outlet Silicone Elbow Hose
1x V-Band Clamp, EFR Exhaust Outlet
1.65’ Vacuum Hose, Silicone 4mm
2x Screw, M8 x 1.25 x 16 Socket Head
2x Nut, M6 x 1.0 Flanged Nylon Locknut
1x Stainless Steel Hose Clamp – SAE #32
1x Stainless Steel Hose Clamp – SAE #36
2x Nut, M6 x 1.0 Flanged, Serrated
2x Screw, M6 x 1.0 x 25 Socket Head
What you need:
- Upgraded intercooler such as mountune PN 2363-IC-MR1
- Cobb Accessport and a competent tuner.
- mountune Intake or suitable option PN 2536-FHF-AA
Disclaimer:
As with any upgrade of this type, additional strain is placed upon your engine and drive train. While we have thoroughly tested and validated the 6258A upgrade without issues, additional power, cylinder pressure and temperatures may cause engine damage and/or complete failure. It is advised that you upgrade your internal engine components and drive train to support the additional power and performance. For motorsport and track use, it is strongly recommended to upgrade your engine internal components to avoid catastrophic engine failure. Please note the use of the BorgWarner EFR 6758 turbocharger has not been validated by Mountune. This product is for race and track use only.
WARNING:
This part has been designed and is intended for off-highway application only. Installation of this part on a vehicle that is driven on public roads may violate U.S. and Canadian laws and regulations relating to emission requirements and motor vehicle safety standards. Click Here for Emissions compliance information.
mountune MRX Turbocharger Upgrade Q &A
1. Does the stock clutch handle the power?
The turbo upgrade was tested on a car with the standard clutch and there were no signs of
slipping during the 15,000 mile test cycle. Driving style and use would also have an effect on
the clutch life and performance.
2. Will the stock transmission be OK with the turbo kit?
The turbo upgrade was tested on a car with the standard transmission and there were no
signs of any issues during the 15,000 mile test cycle. Driving style and use would also have
an effect on the life of the transmission.
3. Can I use my original or other aftermarket intake?
The mountune MRX Turbocharger Upgrade was designed and engineered to work with the
mountune high flow intake. However other intake options may be compatible with some slight
modifications to the intake hose assembly or the intake itself.
4. Does the mountune MRX Turbocharger Upgrade have a C.A.R.B. EO?
The mountune MRX Turbocharger upgrade does not have a C.A.R.B. EO and therefore is for
motorsport use only.
5. I already have a BorgWarner EFR Turbocharger. Can I just buy the base components?
The BorgWarner EFR Turbocharger included in the mountune MRX Turbocharger upgrade
has been configured by our engineers with the correct fittings along with unique wastegate
mounting solution. Additionally, we have pre-adjusted the wastegate tension to ensure
reliable performance within the parameters we have tested. To ensure the upgrade's
performance we do not offer the kit without the turbocharger.
6. Are there options for larger or different turbochargers?
The mountune MRX Turbocharger upgrade has been configured to offer well balanced
drivability for a front wheel drive platform coupled with extreme performance using the BorgWarner EFR 6258A turbocharger.
Additionally the upgrade was engineered to be compatible with the vehicle's stock fueling system. While the
turbocharger (6258A) included in the MRX Upgrade is capable of performance up to 450hp, the
vehicle’s original fueling system is not without additional devices or special fuels.
However we do acknowledge those that have installed additional fueling devises along with upgraded
engines and therefore offer the MRX with the larger EFR 6758 turbocharger. Please note that if you choose
to install the larger EFR 6758 turbocharger, additional technical support from Mountune may not be available.
7. Can I use my existing downpipe or another manufactures downpipe?
The size and exit angle of the exhaust flange on the larger turbocharger requires a downpipe
to meet the specific requirements of the BorgWarner EFR 6258 series Turbocharger. The
mountune downpipe for the MRX upgrade has been engineered to fit within the space
constraints while offering maximum flow and secure installation. Therefore it is advisable to
use the mountune downpipe option.
8. Is custom tuning available?
Mountune does not offer customer tuning.
9. Can I use the mountune Uprated Air Re-circulation Valve with the MRX Upgrade?
Yes ! The mountune Uprated Air Re-circulation Valve can be ordered and used with the MRX
upgrade. PN 2226-TRV-AA. Please note we have not tested any other manufacturer's
recirculation valve and therefore cannot recommend them at this time.
10. Will this turbo kit void my warranty?
Due to the nature of motorsport and racing product usage the mountune MRX turbo upgrade is not covered by the original factory Ford warranty.
Install this on your ST before the EV’s conquer 
